Yu Liu, a scientist who authored this study, has successfully created artificial memories in the minds of mice. His team did a study in which mice were placed in a distinct colored box, they had memory brain cells activated so they could be regenerated with light, and then they were moved to another color box. In the second box, the scientists shined light into the brains of the mice, and activated the very memory cells that were created in the mice’ brains during their stay in the other colored box.

Simultaneously with activating the memory cells from the first box, the mice were shocked lightly. Then, when they were moved to the first box, the mice had fear that they would be shocked, cause their memories of the first box were activated while they were being shocked in the second box.